Compounds found in Rubia tinctorum include purpurin (oxyalizarin; 1,2,4-trihydroxyanthraquinone), mollugin (6-hydroxy-2,2-dimethyl-2H-naphtho[1,2-b]pyran-5-carboxylic acid, methyl ester), 1-hydroxy-2-methylanthraquinone, 2-ethoxymethylanthraquinone, rubiadin (1,3-dihydroxy-2-methylanthraquinone), 1,3-dihydroxyanthraquinone, 7-hydroxy-2-methylanthraquinone, lucidin (1,3-dihydroxy-2-hydroxymethylanthraquinone), 1-methoxymethylanthraquinone, 2,6-dihydroxyanthraquinone, lucidin3-O-primeveroside [6-(β-d-xylosido)-d-glucoside], alizarin (1,2-dihydroxyanthraquinone), lucidin-O-ethyl ether, 1-hydroxy-2-hydroxymethylanthraquinone 3-glucoside, 2-hydroxymethylanthraquinone 3-glucoside, 3,8-dihydroxy-2-hydroxymethylanthra-quinone 3-glucoside, ruberythric acid (alizarin primeveroside; alizarin glycoside), quinizarin and iridoid asperuloside (Schneider et al., 1979; Kawasaki et al., 1992; Derksen et al., 1998; El-Emary & Backheet, 1998; Marczylo et al., 2000).
A number of compounds have been characterized from the roots of R. tinctorum (the source of commercial madder colour) by various analytical methods. Among these compounds are alizarin, ruberythric acid, purpurin, lucidin, rubiadin, mollugin, 1-hydroxy-2-methylanthraquinone, tectoquinone (2-methylanthraquinone), nordamnacanthal (1,3-di-hydroxy-2-anthraquinonecarboxaldehyde), 1-hydroxy-2-methoxyanthraquinone, 1,3-dihydroxy-2-ethoxymethylanthraquinone, scopoletin (7-hydroxy-6-methoxycoumarin) and the glucosides and/or the primeverosides of these compounds (Kawasaki et al., 1992; Westendorf et al., 1998; Medical Economics Co., 2000). The majority of the anthraquinones present in the plant itself or in plant extracts are glycosides (Blömeke et al., 1992; Westendorf et al., 1998).
A number of compounds have been isolated from M. officinalis. Anthraquinones found in the plant include 1,6-dihydroxy-2,4-dimethoxyanthraquinone, 1,6-dihydroxy-2methoxyanthraquinone, methylisoalizarin, methylisoalizarin-1-methyl ether, 1-hydroxy2-methoxyanthraquinone, 1-hydroxy-2-methylanthraquinone, physcion, 1-hydroxyanthraquinone, 2-methylanthraquinone, 2-hydroxy-3-hydroxymethylanthraquinone, rubiadin and rubiadin-1-methyl ether. Terpenoids found include asperuloside tetra-acetate, monotropein, morindolide and morofficinaloside. Glucosides found include nystose, 1F-fructofuranosylnystose, inulin-type hexasaccharide and heptasaccharide. β-Sitosterol, 24-ethylcholesterol, a ketone (officinalisin) and several amino acids have also been found (Li et al., 1991; Yang et al., 1992; Yoshikawa et al., 1995; Zheng & Dong, 1997; Yao et al., 1998).
No direct information was found on the absorption, distribution, metabolism or excretion of ludicin in experimental animal systems. However, a report has appeared on the oral administration of lucidin 3-O-primeveroside to rats, which resulted in the excretion in the urine of lucidin and (to a lesser extent) rubiadin (1,3-dihydroxy-2methylanthraquinone) (Blömeke et al., 1992).
Lucidin primeveroside is hydrolysed in rats to the aglycones 1,3-dihydroxy-2hydroxymethylanthraquinone (lucidin) and rubiadin, which are excreted in urine. Lucidin is mutagenic in bacteria, mutagenic and genotoxic in cultured mammalian cells and forms DNA adducts in mice. 041b061a72